Red here is a couple pictures of my Silkie roos. Each bird is different for trying to figure out the sex. I knew pretty early on that the 2 in the pictures were roos because their comb & wattles grew pretty fast. In fact out of the 5 Silkie babies I have right now, I suspect 3 are roos. They are just over 6 weeks, but upon inspection today I can see larger comb & wattle development on the 3. So far my experience with comb development has not let me down. Do watch the shape of their head fluff too. Rounded shape is more likely to be female & the males will have little spikey things sticking out the backside of their fluff. How old are your baby silkies?